The present invention relates to a pneumatic tire having an improved wheelrim protector being capable of improving high speed cornering performance, ride comfort and the like.
In a pneumatic tire having a low aspect ratio of less than 50%, as the tire section height is very low, the distance between the wheelrim flange and road surface is short. Therefore, there is a strong possibility that the flange contacts with curbs, objects on the ground and the like, and suffers damage therefrom.
As a technique of preventing wheelrim flanges from such damage, a wheelrim protector (d) as shown in FIG. 19 has been proposed. The protector (d) is disposed in each sidewall portion near the bead (b) and protrudes axially outwardly from the axially outmost end of the flange (jf) and extends continuously in the circumferential direction.
Such protector increases the rubber thickness of the sidewall portion, and a flexible region of the sidewall portion decreases. As a result, ride comfort deteriorates, and shocks received from the road surface during running are more transmitted to the bead portion and the bead durability greatly decreases.
Further, the tire rigidity suddenly alters during cornering if there is occurred a change from a situation wherein the protector does not contact with the flange to a situation wherein the protector contacts with the flange as shown in FIG. 19 by chain line. Therefore, if such change occurs during high speed cornering it becomes difficult to control the behavior of the car.
It is therefore, an object of the present invention to provide a pneumatic tire having a wheelrim protector in which the ride comfort, controllability during high speed cornering and the like are improved.
According to the present invention, a pneumatic tire comprises
a tread portion,
a pair of sidewall portions,
a pair of bead portions,
a carcass extending between the bead portions,
a wheelrim protector provided in at least one of the sidewall portions so as to overhang a flange of a wheelrim when the tire is mounted thereon and to protrude axially outwardly from an axially outer end of the flange, and
the wheelrim protector provided with at least one circumferential slit around the axis of the tire.
In the present invention, the circumferential slit is meant as a circumferentially continuous slit or discontinuous slits having such a length that the circumferential component is larger than the radial component.